1. Field of the Invention
This invention relates to insect traps and particularly to a trap for placement on windowsills inside a structure. More particularly, the invention relates to a trap for flying insects that does not require bait, but uses ambient light to attract insects and water to trap them.
2. Description of the Related Art
Various devices have been made to trap insects such as flies, moths and the like. Many of these traps require bait, often in the form of fermenting liquid. The odor of the fermenting liquid attracts the insects. Examples of such traps are described in U.S. Pat. Nos. 4,360,987, 4,557,069, 4,638,592, 5,231,792, 5,596,833, 5,490,349 and 5,406,743. Many of these traps are unacceptable for use inside structures because of the unpleasant odor of the bait. A fly trap not requiring bait and designed to attach to a window is described in U.S. Pat. No. 5,239,771. While not requiring bait, this trap is of complex design for preventing flies from escaping. Many of the prior art traps are relatively expensive to manufacture because of the complicated configuration required to lure the insects and prevent their escape.
Accordingly, there is a need for a simple, inexpensive insect trap that does not require bait and is suitable for use inside a structure, which will trap flying insects from within the surrounding area. It is an object of the present invention to provide such a trap.
The insect trap of the invention is designed to be used inside a structure such as a barn, shed, house, or other place where it is desired to eliminate flying insects. The trap is designed to be placed on a windowsill, adjacent the window, but can be placed in any location with a suitable flat surface.
In accordance with the instant invention, the insect trap comprises an open-top receptacle for holding a liquid in which the rear wall is flat and has a thin top edge so that when the trap is placed next to a window, the rear wall lies flush against the window. As used herein, the term xe2x80x9cthinxe2x80x9d means a thickness such that there is a substantially smooth transition from the window to the rear wall of the trap. At the lower limit, the edge could actually be sharp, although this is neither necessary nor desirable. Rather the edge need only be sufficiently thin that an insect walking on the window in the direction of the edge is not generally diverted in its path. In a preferred embodiment, the rear wall has a tapered edge at the top enabling the rear wall to lie flush against the window. In use, flies are attracted to the ambient light at the window and fly up and down the window in search of a way out. When the flies encounter the thin top edge of the rear wall of the trap, they continue down and fall into the water in the trap and drown. Preferably the rear wall of the trap extends upward from a plane defined by the top edge of the other walls and is formed of transparent material which simulates the window to decrease panic and allow insects to continue down into the water. The transparent material also increases the level of ambient light at the window. Supports made of suitable material may be attached to the bottom or rear of the trap for securing the trap to the window. A deodorizing solution may be added to the water to act as a general air freshener and to eliminate the odor of decomposing insects in the trap.
Various additional features can be included in further embodiments of the invention. One such feature is an insect trap designed to hold water in which baffles are situated inside the trap to prevent excessive water movement, especially during filing and emptying the trap.
Another feature of the invention is an insect trap in which a disposable liner is used to hold the water. The liner preferably has holes covered with a removable seal so that the water can be drained from the liner after use to allow easy disposal of the dead insects.
An additional feature of the invention is a method of trapping insects in which the trap is partially filled with water and surfactant and placed on a windowsill so that the rear of the trap is flush with the window. The surfactant reduces the surface tension of the water and prevents insect from walking across the water to escape.